THE FUTURE OF COMPUTER

MODELING OF COASTAL WETLAND,

ESTUARINE, AND RIVERINE SYSTEMS

Ehab Meselhe November 2015

TEAM EFFORT

• The Water Institute of the Gulf – Natural Systems Modeling and Monitoring

• Ehab Meselhe

• Hoon Jung

• Ashok Khadka

• Kazi Sadid

• Katelyn Costanza

• Fei Xing

– Physical Processes and Sediment Systems • Mead Allison

• Cyndhia Ramatchandirane

• Dallon Weathers

• Brendan Yuill

– Coastal Ecology • Tim Carruthers

• Melissa Baustian

• Ann Hijuelos

• Leland Moss

• Kelly Darnell

• Caitlin Pinsonat, Blake Thompson, Dominque Henson, Kinsey Vernon, Shannon Matzke

TEAM EFFORT

• Deltares – Johannes Smits

– Bas van Maren

– Valesca Harezlak

– Michel Jeuken

• University of Louisiana-Lafayette – Scott M. Duke-Sylvester

– Jenneke M. Visser

– Mark Hester

• Louisiana State University – Sibel Bargu and Jamal Mathurin

– Dubrakvo Justic

– John White

– Sam Bentley

– Tommy Blanchard

CONCLUSIONS/MAIN

FINDINGS/CHALLENGES

• Expectations are growing rapidly:

– More physical and ecological processes

– Higher spatial resolution

– Longer temporal projections into the future

– Interaction and integration

• Concerns about computational run time

• Reporting exact numbers and translation into $

4

CONCLUSIONS/MAIN

FINDINGS/CHALLENGES

• Science challenges:

– Knowledge gaps

– Compromise between efficiency and accuracy

• Communication/application challenges:

– Uncertainty

– Environmental changes – plausible future scenarios

5

PROJECT GOALS

Produce a validated model capable of simulating:

Morphological processes during the creation of a

new delta and wetland areas

Nutrient effects to wetland vegetation, soil, and

estuarine primary producers of Breton Sound and

Barataria Basins.

MODELING APPROACH

Hydrodynamics

Morphodynamics Nutrient Dynamics

Integration of Nutrient and Morphodynamic Modules to

assess performance of restoration strategies

Vegetation

MODEL OVERVIEW

8

D-WAQ MODEL SETUP

SUBSTANCES

8 Phytoplankton Groups:

- Freshwater Diatoms, Freshwater Flagellates, Green Algae, Microcystis, Anabaena

- Marine Diatoms, Marine Flagellates, Dinoflagellates

Water Quality Variables:

- TOC, POC, DOC,

- TN, PON, DON, NH4, NO3

- TP, POP, DOP, PO4

- Si, Silt, Clay, TSS

- DO, Chl a

D-WAQ: SEDIMENT/SOIL LAYERS

Sediment Soil

VEGETATION MODELS

11

LAVEGMOD.ROOTSHOOT AND VEGMOD

Total

Biomass

Spartina patens

Aboveground

Belowground

Biomass

Allocation POM in water

column

POM in soil

Mortality

(VEGMOD) (LaVegMod.RootShoot) (VEGMOD)

12

LAVegMod.DM & Marsh Types

Focus on 7 emergent marsh taxa:

Fresh: Sagittaria latifolia (arrowhead)

Zizaniopsis miliacea (giant cutgrass)

Intermediate: Sagittaria lancifolia (bulltongue)

Phragmites spp. (common reed)

Typha spp. (cattail)

Brackish: Spartina patens (wiregrass)

Saline: Spartina alterniflora (oyster grass)

Submerged Aquatic Vegetation (SAV)

• Generically modeled

13

D-FLOW with SED-

ONLINE MORFAC 40 – approx. 2 yrs. – 1 day

Initialization phase

Iteration phase

* This runs outside the 1-month aim of the iteration phase (can be run long in advance, irrelevant any for scenarios)

* Aim: 1 wall-clock-month to run 50 yrs. of combined D-FLOW, SED-ONLINE, D-WAQ & LAVegMod.DM modules

Field input

Equilibrium bathymetry

Equilibrium stratigraphy

D-FLOW 1 yr. – 4 days

LAVegMod.DM Few hours

Annual hydro conditions

Trachytopes through scripting

Updated initial conditions for each iteration, includes:

- Stratigraphy (& bathy)

- Trachytopes

T = 50 yrs. = N * Δt Assumed N = 5 & Δt = 10 yrs.

D-FLOW with SED-

ONLINE MORFAC 40 – Δt yrs. – approx. Δt/2 in days

D-FLOW 1 yr. – 4 days

Updated bathymetry & stratigraphy

Annual hydro conditions

LAVegMod.DM Few hours

Trachytopes through scripting

D-WAQ # of yrs. – approx. 10 hrs. per year

total # of yrs. limited by D-FLOW with SED-ONLINE track

Vegetation biomass

Multiplied by Δt

Updated bathymetry & -

stratigraphy, using

vegetation biomass

Initial trachytopes Based upon bathymetry

Flowchart 2

Simple multiplication can go wrong due to physical limits and non-linear effects

Advised to explore the non linear behavior and the use of LaVeg results to limit the physical results

DELFT-3D MODEL DOMAIN AND

GRID

PROJECT TIMELINE

• Modeling Work: 18 months

Model Milestone Deadline

Project Begins March 2014

Data Collection Begins June 2014

Model Setup September 2014

Model Operational January 2015

Model Testing March 2015

Model Calibrated April 2015

Model Validated May 2015

Production Runs Begin (7 scenarios) June 2015

Production Runs End (7 scenarios) September 2015

Reports Submitted and Project Ends December 2015

CONTINUOUS DATA COLLECTION NETWORK

RECAP AND UPDATE

Breton Barataria

ESTUARINE TRANSECTS - 2015

19

Density, fraction of silt/sand/clay, and organic content for core #3 in

Baretaria Bay. This core was taken in the marshland approximately 0.5 m

above MSL.

VALIDATION FOR THE RIVER:

YEAR 2014

• Suspended sediment transport rate at Belle Chasse

20

WATER LEVEL VALIDATION (BARATARIA) - 2014

CRMS4218

CRMS3617

CRMS4529

WATER LEVEL VALIDATION FOR BARATARIA BAY

AND BRETON SOUND BASINS- 2014

Daily Average

Bias (ft) Corr Coef (r) RMSE (ft) Mean -0.04 0.61 0.44

stdev 0.34 0.16 0.15

min -0.80 0.14 0.20

max 0.90 0.84 1.00

Sites, n = 95

SALINITY VALIDATION (BARATARIA) – 2014

(DAILY AVERAGE)

WATER INSITUTE STATIONS

SALINITY VALIDATION FOR BARATARIA BAY AND

BRETON SOUND BASINS- 2014

Daily Average

Bias (ppt) Corr Coef (r) RMSE (ppt) Mean 1.90 0.59 3.92

Stdev 2.78 0.27 1.94

min -5.00 0.03 0.40

max 7.60 0.98 8.30

Weekly Average

Bias (ppt) Corr Coef (r) RMSE (ppt) Mean 1.88 0.62 3.85

Stdev 2.77 0.27 1.92

min -5.40 0.04 0.40

max 7.60 0.99 8.10

Monthly Average

Bias (ppt) Corr Coef (r) RMSE (ppt) Mean 1.91 0.67 3.65

Stdev 2.75 0.27 1.94

min -5.50 0.06 0.00

max 7.50 0.99 8.10

Sites, n = 93

MORPHOLOGIC CHANGE IN

CAERNARVON: YEAR 2011

25

Vertical Erosion/Accretion in 2011 (centimeter)

• Vertical Accretion (mineral+organic)

between 0.75 cm/yr. and 1.57 cm/yr (1996

to 2000, Lane et al. 2006)

• The model predicted vertical accretion

(mineral) in the year 2011 is approximately

1.71 cm/yr.

Source: Lake Pontchartrain Basin Foundation

MORPHOLOGIC CHANGE IN

CAERNARVON: YEAR 2014

26

Vertical erosion/accretion in 2014 (centimeter)

• Vertical Accretion (mineral + organic) between 0.75

cm/yr and 1.57 cm/yr (Day et al., 2009, Lane et al.

2006)

• The model predicted vertical accretion (mineral) in

the year 2014 is approximately 0.85 cm/yr.

• Land building is less in 2014: The diversion was not

in operation after March 2014

Source: Lake Pontchartrain Basin Foundation

WATER QUALITY OBSERVATION

STATIONS FOR CALIBRATION:

YEAR 2009

WATER QUALITY CALIBRATION

BB-WAQ-18 (GRAND ISLE)

WATER QUALITY CALIBRATION

BS-WAQ-05 (LAKE LERY)

PHYTOPLANKTON

COMPOSITION

30

0

20

40

60

80

100

Com

posi

tion

(%)

BS1 August 2014

Modeled

Observed

0

20

40

60

80

100

Com

posi

tion

(%)

BS3 August 2014

Modeled

Observed

0

20

40

60

80

100

Com

posi

tion

(%)

BS11 August 2014

Modeled

Observed

BRETON

CRMS 0135

VEGETATION BIOMASS CHANGE

Feb. Sep. Dec.

Spartina

alterniflora

Spartina

patens

Sagittaria

lancifolia

SALINITY ANIMATION- 2014

WATER QUALITY ANIMATIONS

34

35

WATER QUALITY ANIMATIONS

SEDIMENT DIVERSION

PRODUCTION RUNS (PR)

PR ID Description Operating Plan Design Discharge (cfs)

Sea Level

Rise Subsidence Rate

PR1 Mid-Barataria Less Aggressive 75K Intermediate 20% into range

FWOP/PR2 Future Without Project N/A (No Diversions)

N/A (No Diversions) Intermediate 20% into range

PR3 Mid-Breton Less Aggressive 35K Intermediate 20% into range

PR4 Lower-Breton Less Aggressive 50K Intermediate 20% into range

PR5 Lower-Barataria Less Aggressive 50K Intermediate 20% into range

PR6 All Four Diversions Less Aggressive 35K,50K,50K,75K Intermediate 20% into range

PR7 All Four Diversions Aggressive 35K,50K,50K,75K Intermediate 20% into range

PR8 Marsh Creation/Dredge Only N/A (No Diversions) N/A (No Diversions) Intermediate 20% into range

PR9 No Vegetation (20 yrs) Less Aggressive 35K,50K,50K,75K

Intermediate 20% into range

Less Aggressive = operation for 5 months

Aggressive = operation all year

PR8 = PR6 diversion footprints with sediment from 11 river bars

,0

10000,0

20000,0

30000,0

40000,0

50000,0

60000,0

70000,0

80000,0

,0

200000,0

400000,0

600000,0

800000,0

1000000,0

1200000,0

,0 1000,0 2000,0 3000,0 4000,0 5000,0 6000,0 7000,0 8000,0

Sed

imen

t D

iver

sio

n D

isch

arg

e (C

FS

)

Mis

siss

ipp

i Riv

er D

isch

arg

e (C

FS

)

Hours

Less-Aggressive Operations

MISSISSIPPI RIVER

DAVIS POND

CAERNARVON

MID-BRETON

MID-BARATARIA

LOWER-BARATARIA

LOWER BRETON

OPERATION PLAN – LESS AGGRESSIVE

July

5th

Feb

20th

WATER LEVEL

MID BARATARIA OUTFALL AREA, YEAR 50

MBA: Mid Barataria

MBS: Mid Breton Sound

LBS: Lower Breton Sound

LBA: Lower Barataria

Note: Red Vertical Line represents annual end of

less aggressive operational schedule

Difference Between Future Without Project and 4 Diversions (Year 50)

WSE DIFFERENCE: PR6-PR2(FT)

DELFT: PR 6-PR2 DIFFERENCE

AT YEAR 50

LAND BUILDING

Organic Matter + Mineral Material

41

MRDM DELFT

LAND CHANGE - FWOP (YEAR 0-

50)

43

LAND BUILDING MAPS AT YEAR 50:

PR1

44

LAND BUILDING MAPS AT YEAR 50:

PR3

45

LAND BUILDING MAPS AT YEAR 50:

PR6

WATER QUALITY – TSS: 2070

BS11

BS6

BB15

BB11

BB5 BS11

BS6

BB15

BB11

BB5

WATER QUALITY – TSS: 2070

April

October

PR1 –PR2 PR6 –PR2 PR7 –PR2

WATER QUALITY – NO3: 2070

April

PR1 –PR2 PR6 –PR2 PR7 –PR2

October

WATER QUALITY – PO4: 2070

April

PR1 –PR2 PR6 –PR2 PR7 –PR2

October

WATER QUALITY – Chl a: 2070

PR1 –PR2 PR6 –PR2

April

PR7 –PR2

October

PR6 ANIMATION: TSS

51

PR6 ANIMATION: Chl a

52

PR2 : Future Without Projects

2070

SAV

Fresh

Intermediate

Brackish

Saline

53

Zones represent dominance, not complete replacement

54

PR2

FWOA

PR6

Mid & Lower

Diversions

SAV

Fresh

Intermediate

Brackish

Saline

SAV

Fresh

Intermediate

Brackish

Saline

2070

CLOSING REMARKS

• Use modeling/analysis to identify:

– Science knowledge gaps

– Potential areas of model improvements

– Better integration techniques

– Design of data collection campaigns

• Engage and solicit input along the way from all

involved parties

• Continue to explain/communicate model

uncertainties and outcome uncertainties

55

THANK YOU

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